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(No Model.)

H; AIKEN.

BLADE FOR SHEARS. No. 331,934. P atent'edDen. 8, 1885.

A -ml W333i? INVENTO? WWW ml? M HEKRY AIKEN, OF PITTSBURG, PENNSYLVAXLL BLADE FOR SHEARS.

SPEGIFICATIO'N forming part of Letters Patent 310.331334, dated December 8, 1885.

A pplieation tiled October 1. 1855. Serial No. 178,721. (No model.)

To aZZ 20710722 it may concern:

Be it known that I, HENRYAIKEN, residing at Pittsburg. in the county of Allegheny and State of Pennsylvania, a citizen of the United States, have invented or discovered certain new and useful Improvements in 'l'llades for Shears, of which improvements the following is a specification.

In the accompanying drawings, which make part of this specification, Figure 1 is a transverse sectional elevation of a portion of the upper or moving jaw ot a power shear-niachine. Fig. 2 is a similar view of the lower or stationary jaw. Figs. 3, i, and 5 are Slllll: lar views otjaws of a shear, showing modified forms of the cutting-blade.

The invention herein relates to certain improvements in the construction and manner of Securing the cuttingblades of powershears, and has for its object such a construction of the cutting-blade as will enable it to be readily and easily constructed and finished, and atthe same time provide in the same structure an increased number of cutting-edges, thereby increasing the length of service of the blade; and it is a further object ofsaid invention so to construct the jaws and blade of the shears that the latter may be easily and quickly removed for the purpose of either bringing a new cutting-edge into operative position or for inserting an entirely new blade; and to these ends my invention consistsin the construction and combination of parts, substantially in the manner hereinafter more i'ully described and I claimed.

My improved blade consists of two or more rectanguiar bars of steel, 1 and 2, and a connecting web, neck, or portion, 8. In the form oi blade shown in lrigs. l and 2 the bars 1 and 2are so arran rul that the diagonals of one bar will be parallel. with the corresponding diagonals ol' the other bar, the connecting web or portion being prolongations of adjacent corners. The length ol this connecting web or portion is immaterial, as the shear parts or members i. and 2 may he made so as to touch at their corners or sides. In this web or connecting portion are formed grooves or recesses 4 on opposite sides thereof, for the reception of correspondinglyshupcd lugs on the shoe 5 and clamping plate 6, whereby the blade is attached to the jaws of the shears.

As the jaws of the shears and the blade-attaching devices are similar as regards the at tachment of blades, the description of the manner of connecting one blade will be sufficient. In the face of the jaw is formed a recess, 7, against the back wall of which is placed the shoe 5, the upper edge of such shoe resting against the upper wall of the recess, as shown in Fig. 1. The lower edge of the shoe is provided with an outwardly projecting flange, 8, having its upper corner rounded to fit the circular groove in the web3 of the cutting-blade. The blade, resting on thefiange S, is held in position by the clamping-plate 6, provided with-a retainingrib, 9, having its inner corner round to correspond with the curvature of the groove in the opposite side of the web 3. The upper end of the plate 6 rests against the upper wall of the recess 7, thus providing a firm support as against the upward thrust ofthe knife in cutting. A. prtion of this upward thrust is transferred to the shoe by means of the rib 10, formed on the shoe near its upper end, said rib being constructed to fit within the groove 11, formed in the inner face of the clamping-plate. The sides of the rib 10 and the groove llare formed tapering, as shown, so as to provide for slight inequalities in the thickness of the web and bar portions in different blades. The clamping-plate and shoe are held in place by ascries of bolts, 12, passing through holes in the plate, shoe, and clampingjaw, as shown.

The relative arrangement of parts above described in connection with the upper or movable jaw will be reversed in the lower jaw, as will be readily understood. \Vhen the edge of the blade (shown in cutting position in F1 1) becomes chilled or. injured, the blade can be turned end for end, thereby bringing a new edge into operative position. and when the second edge is dulled the blade can be turned over, thus bringing one of the cutting-edges of the other bar into operative position, and finally,a fourth edge may be brought into operation by again turning the blade end for end.

In Fig. 5 is shown a form of blade embodying the same principles of construction as are shown in Figs. 1 and 2, but composed of double the number of bars and cutting-edges. In this form ofblade the groovesat are formed between two zn'ljacent bars or shearing members ICO in the same side, instead of between two di agonally-arranged bars, and the positions of the supportingflange 8 and the retaining-rib 9 are correspondingly changed, as shown. Eight cutting-edges can be brought into operative positions in using this form of blade.

In Figs. 8 and 4 are shown blades embodying the same general principles of construction, but having only two cutting-edges. The web or connecting portion 3, uniting the bars 1 and 2 in Figs. 3 and 4, is a prolongation of adjacent sides of the bars, the bars in Fig. 3 being arranged in different vertical plane, and in this case the web is laterally extended on one side, the grooves 4 being formed in oppositesides of the lateral extension, as shown. The shape and location of the supportingflange 8 and retaining-rib 9 are made to conform with changes in the shape of the blade.

Other forms of blades than those shown and embodying the same principles of construction may be made, and therefore'l do not wish to limit myself to the exact forms of blades, as shown and described.

These blades can be easily made by rolling in suitable grooved rolls to the exact size and shape desired, and can then have their faces ground to produce the requisite cutting edge. By thus constructing the blades the laborious and expensive method of forming and repairing the blades for shears now in use is avoided, such method consisting in drawing the temper of the bar from which the cutter is to be made, forging such bar to shape, retempering the forged bar, and then straightening and grinding the cutting-edge.

I claim herein as my invention- 1. A blade for shears, consisting of two or more right-angular or approximately rightangular steel bars or shearing members united in an integral structure by a web or connecting portion, substantially as set forth.

2. A shearingblade having in combination two or more right-angular or approximately right-angular shearing parts or members and a groove or recess back of the cutting-edge of each such member, such grooves or recesses being of like construction in each blade and in like relationship to the contiguous cutting-- supportingflange and a clamping-plate hav ing a retaining-rib, said flange and rib being constructed to fit the grooves or recesses in the blade, substantially as set forth.

4. Ashearingblade having gin combination two or more right-angular or approximately right angular shearing parts or members united at contiguous corners in an integral structure and a groove or recess back of each part or member, such grooves or recesses being of like construction in each blade and in like relationship to the contiguous cutting edge, substantially as set forth.

In testimony whereof I have hereunto set my hand.

HENRY AIKEN.

NVitnesses:

DARWIN S. WOLCOTI, R. H. WHITTLEsEY. 

